A urinary bladder tube is used on patients who are unable to urinate. There are many causes of the inability to urinate. Frequently, surgery or other invasive procedures produce such an effect. Generally, the origin of such a condition differs with age and gender. For example, the inability to urinate in men is commonly caused by a blockage of the urethra passageway by an enlargening prostate. In females, the condition may occur after delivery of a baby. And, in small children, a congenital abnormality obstructing the bladder neck or urethra can produce the condition.
After major surgery, it is advantageous to continuously drain the bladder. Continuous drainage of the bladder is also preferred where medical conditions dictate the necessity of monitoring a patient's urine output. It is well known that close measurement of urine output provides a direct correlation to kidney functions and careful monitoring allows one to identify and prevent kidney failure.
It is important to drain the bladder by an indwelling catheter after prostate or bladder surgery. An indwelling Foley type catheter is usually the catheter of choice. U.S. Pat. No. 5,300,022 to Klapper et al and incorporated herein, shows an improvement over the Foley catheter by providing a second lumen for continuous delivery of a sterile irrigating solution directly into the bladder, and preventing any mixture with the main drainage lumen, thus avoiding any reintroduction of harmful bacteria into the bladder during irrigation.
U.S. Pat. No. 4,701,162 issued to Rosenberg and incorporated herein, shows a Foley catheter with two lumens, one for drainage and one for inflation of the balloon. Having separate lumens for drainage and inflation is common in the prior art. U.S. Pat. No. 5,098,379, which is incorporated herein by reference, discloses a Foley catheter having a balloon portion and a lubricated resilient sleeve. U.S. Pat. No. 5,269,770, which is incorporated herein by reference, shows a dual lumen system and balloon Foley catheter for releasing a bactericidal agent. Similarly, U.S. Pat. No. 5,269,755 which is incorporated therein by reference, shows a Foley urinary catheter with a dual membrane delivery system that allows bactericidal agents to diffuse into the urinary tract.
One thing is clear in the prior art of Foley urinary catheters: none of them teach a collapsible device.
An indwelling catheter drains the bladder and diverts the urine from the wound. Moreover, the bladder can be either continuously irrigated with a three way foley catheter or hand irrigated at discrete moments when desired. In the three way catheter, one port used is connected to a large fluid reservoir and the other port is used for drainage of the returned fluid. The speed of irrigation can be controlled by different mechanisms or different pumps.
In certain patients the bladder must be drained for many years, as in patients with spinal cord lesions. If the bladder is not drained, the pressure inside it will build up and obstruct the kidneys. Continuous kidney obstruction could end in renal failure and death in only a few weeks. Furthermore, the catheter is used to clear blockages and constrictions of the urinary tract.
Therefore, the use of indwelling catheter is very important and could be life saving.
However, there are many serious draw backs to the stiff indwelling catheter. First, it is painful and certain patients cannot tolerate the catheter. Second, a stiff hollow indwelling catheter invites micro-organisms to invade the bladder and kidneys which may cause a serious infection. Third, for patients who are unable to tolerate the stiff catheter, a hole in the bladder must be created to drain the bladder directly through the anterior abdominal wall. This is a serious procedure and exposes the patient to unnecessary risks of other complications.
Thus, it would be ideal if a Foley catheter was stiff enough to be introduced, but collapsed after insertion. The urethra is naturally in a state of collapse at rest. The present invention will mimic the urethra's physiological status. The pain or discomfort from an indwelling catheter will be reduced. In addition, the incidence of bladder or kidney infection is minimized.
A naso-gastric tube is currently used to drain or feed a stomach and is necessary after almost any abdominal or bowel surgery. Abdominal or bowel surgery will put the entire gastro-intestinal tract into a state of shock for a period ranging from one day to several days. During this period of shock, the entire gastro-intestinal tract will go into a state of paralysis, namely paralytic ileus. If left unchecked, paralytic ileus could lead to death. But, removing the stomach content with a naso-gastric tube allows the stomach and bowel to recover from their state of paralysis.
Stomach tubes are life saving devices. The stomach, bowel, gall bladder and pancreas produce more than ten liters of secretions per day. When in a state of paralysis, the stomach and bowel fill up with these secretions. Unless drained, the stomach and bowel will distend by at least ten liters per day. It is known in the arts that draining the stomach content will collapse the stomach and decrease acid secretion. This in turn will decrease the alkaline secretions from the bowel, gall bladder and pancreas. Decreasing the secretions conserves the use of the body's immune system, namely, important electrolytes and enzymes are saved for other uses. Moreover, collapsing the gastro-intestinal tract speedens recovery from paralytic ileus. It is known in the arts that a patient will likely die within a few days if paralytic ileus is not treated. Since the nineteenth century, stomach tubes have been used after abdominal or bowel surgery to preserve life until the gastro-intestinal tract recovers.
In addition, a naso-gastric tube is necessary for feeding some debilitated patients. These patients are either in a state of coma or are unable to swallow. The naso-gastric tubes are left in as long as needed. The period for such tube feeding is often a few days or weeks, but it may extend to months and even indefinitely for longterm comatose patients. Furthermore, the tube may be used to clear blockages or restrictions of the gastro-intestinal tract.
And like the prior art for urinary catheters, one thing may be gleaned from the prior art for naso-gastric tubes: none of them teach a collapsible device.
Therefore, the use of naso-gastric tubes to drain or feed the stomach of a patient is very important and often life saving.
However, there are serious draw backs to today's naso-gastric tube. First, the tubes are stiff and therefore very uncomfortable. In fact, they are sometimes so uncomfortable that a patient is not able to tolerate it.
Second, the stiffness of today's naso-gastric tubes causes complications by allowing some of the stomach secretions to move up and down the esophagus during the increase or decrease in the intra-abdominal pressure. The strong esophageal circular muscle sphincter, located at the junction of the stomach and esophagus, usually prevents the movement of acid up and down the esophagus. However, the stiff tube restricts the action of this powerful constricting sphincter and thus allows acid to move up and down the esophagus.
Third, the stiffness of the tube can be a source of infection.
Fourth, when a patient cannot tolerate a naso-gastric tube, the nose, mouth and esophagus must be bypassed by making a hole directly into the stomach. This is a serious procedure and brings more risk to the patient because making a hole in the stomach can cause digestion of the skin.
Thus, it would be ideal if a naso-gastric tube was stiff enough to be introduced into the stomach, but then collapses after insertion. That is what the present invention teaches. The esophagus is naturally in a state of collapse at all times except when food is swallowed or vomited. During eating, the esophagus contracts to propagate swallowed food down and into the stomach. During vomiting, the esophagus reverses the propagation contraction to project the food up and out of the stomach. The present invention will mimic the esophagus's physiological status. The pain or discomfort from a stiff tube will be minimized. In addition, the risk of infection or other complications will be reduced.